1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
|
; Part of Scheme 48 1.9. See file COPYING for notices and license.
; Authors: Richard Kelsey, Jonathan Rees, Mike Sperber
; This file should be loaded into the bootstrap linker before any use
; of DEFINE-STRUCTURE. Compare with env/init-defpackage.scm.
(define (evaluate-transformer exp env)
(if (and (pair? exp)
(eq? (car exp) 'syntax-rules))
(if (pair? (cdr exp))
(let ((subkeywords (cadr exp))
(rules (cddr exp)))
(if (and (list? subkeywords)
(every name? subkeywords))
(call-with-values
(lambda ()
(process-rules exp name? (lambda (x) x) eq?))
(lambda (code inserted)
;; Pair of the procedure and list of auxiliary names
(cons
(eval `(let ((transformer ,code))
(lambda (exp rename compare) ; turn 4-arg transformer into 3-arg transformer
(transformer exp name? rename compare)))
env)
inserted)))
exp))
exp)
(eval exp env)))
(define-syntactic-tower-maker
(lambda (clauses names)
(let ((env (interaction-environment)))
(delay
(begin (if (not (null? clauses))
(warn "a FOR-SYNTAX clause appears in a package being linked by the cross-linker"
`(for-syntax ,@clauses)))
(cons evaluate-transformer env))))))
(define-reader read)
|
